Static liquid piston compressor and expander systems and methods for same

Abstract

A liquid piston system includes a liquid piston compressor/expander assembly and a drive mechanism. The liquid piston compressor/expander assembly includes a reciprocating cylinder coupled with the drive mechanism and a static liquid piston received in the cylinder cavity. The static liquid piston includes a piston face configured to carry liquid piston fluid. The reciprocating cylinder is configured to move relative to the static liquid piston between contracted and expanded positions. In a compressor, at the expanded position the cylinder head is withdrawn from liquid piston fluid and the cylinder cavity is filled with the compressible fluid. In the contracted position the cylinder head of the reciprocating cylinder is near the liquid piston fluid and the compressible fluid is compressed. With an expander, in the contracted position the compressible fluid is introduced to the cylinder cavity and the expanding compressible fluid moves the reciprocating cylinder to the expanded position.

What is claimed is: 
     
         1 . A liquid piston compressor system comprising:
 a drive mechanism;   a compressor assembly coupled with the drive mechanism, the compressor assembly includes:
 a reciprocating cylinder coupled with the drive mechanism, the reciprocating cylinder includes a cylinder cavity and a cylinder head, and 
 a static liquid piston received in the cylinder cavity, the static liquid piston includes a piston face configured to carry liquid piston fluid; and 
   wherein the reciprocating cylinder is configured to move relative to the static liquid piston between contracted and expanded positions to compress a compressible fluid:
 in the expanded position the cylinder head is withdrawn from liquid piston fluid and the cylinder cavity is filled with the compressible fluid, and 
 in the contracted position the cylinder head is near the liquid piston fluid and the compressible fluid is compressed. 
   
     
     
         2 . The system of  claim 1  comprising liquid piston fluid carried on the piston face. 
     
     
         3 . The system of  claim 2 , wherein the liquid piston fluid includes a liquid piston ferrofluid, and the static liquid piston includes a retention magnet configured retain the liquid piston ferrofluid along the piston face. 
     
     
         4 . The system of  claim 2 , wherein liquid piston fluid is a heat sink or heat source. 
     
     
         5 . The system of  claim 4 , wherein the compressor assembly includes a heat exchanger in communication with the liquid piston fluid, and the heat exchanger is configured to extract heat from the liquid piston fluid heated by the compressed compressible fluid. 
     
     
         6 . The system of  claim 5  comprising a compressible fluid, and the compressible fluid is isothermal between the expanded and contracted positions according to the liquid piston fluid heat sink and the operation of the heat exchanger. 
     
     
         7 . The system of  claim 1 , wherein the reciprocating cylinder includes a porous heat transfer media within the cylinder cavity. 
     
     
         8 . The system of  claim 7 , wherein the porous heat transfer media consists of one or more of tubes, posts, fins, interlaced tubes, interlaced posts, interlaced fins, tilted interrupted plates, profiled cylinder cavity walls, metallic foam or wire mesh. 
     
     
         9 . The system of  claim 7 , wherein the porous heat transfer media includes a phobic coating with respect to the liquid piston fluid. 
     
     
         10 . The system of  claim 1 , wherein the compressor assembly includes one or more spray ports configured to spray a heat sink fluid into the cylinder cavity. 
     
     
         11 . The system of  claim 10  comprising liquid piston fluid housed on the piston face, and the sprayed heat sink fluid is the same as the liquid piston fluid. 
     
     
         12 . A liquid piston compressor assembly comprising:
 a reciprocating cylinder including a cylinder cavity and a cylinder head;   a static liquid piston received in the cylinder cavity, the static liquid piston includes:
 a piston face, 
 a liquid piston ferrofluid along the piston face, and 
 a retention magnet; and 
   wherein the reciprocating cylinder is configured to move relative to the static liquid piston between contracted and expanded positions:
 in the expanded position the cylinder head is withdrawn from the liquid piston ferrofluid, 
 in the contracted position the cylinder head is near the liquid piston ferrofluid, and 
 the retention magnet is configured to retain the liquid piston ferrofluid along the piston face in each of the expanded and contracted positions and during movement therebetween. 
   
     
     
         13 . The assembly of  claim 12 , wherein the liquid piston ferrofluid includes a liquid base and a plurality of ferrous particles suspended in the liquid base. 
     
     
         14 . The assembly of  claim 13 , wherein the liquid piston ferrofluid includes a surfactant. 
     
     
         15 . The assembly of  claim 12 , wherein the reciprocating cylinder includes a porous heat transfer media within the cylinder cavity. 
     
     
         16 . The assembly of  claim 15 , wherein the retention magnet is configured to extract the liquid piston ferrofluid from interstitial locations of the porous heat transfer media with movement of the reciprocating cylinder between the contracted and expanded positions. 
     
     
         17 . The assembly of  claim 12  comprising a heat exchanger in communication with the liquid piston ferrofluid, wherein the heat exchanger is configured to extract heat from the liquid piston ferrofluid, the liquid piston ferrofluid heated by compression of a compressible fluid with movement of the reciprocating cylinder between the expanded and contracted positions. 
     
     
         18 . The assembly of  claim 25 , wherein the compressible fluid is isothermal between the expanded and contracted positions according to the liquid piston ferrofluid and the operation of the heat exchanger. 
     
     
         19 . A method of using a liquid piston compressor system comprising:
 introducing a compressible fluid at a first temperature to a cylinder cavity of a reciprocating cylinder in an expanded position:   isothermally compressing the compressible fluid within the cylinder cavity, compressing including:
 moving the reciprocating cylinder toward a contracted position relative to a static liquid piston to compress the compressible fluid, and 
 extracting heat from the compressible fluid, the heat generated with compression of the compressible fluid; and 
   evacuating the compressed compressible fluid from the cylinder cavity at a second temperature near the first temperature.   
     
     
         20 . The method of  claim 19 , wherein the static liquid piston includes liquid piston fluid, and extracting heat from the compressible fluid includes:
 transferring heat from the compressible fluid to material of the reciprocating cylinder,   transferring heat to the liquid piston fluid from the material of the reciprocating cylinder,   cycling the heated liquid piston fluid through a heat exchanger, and   extracting heat from the liquid piston fluid at the heat exchanger.   
     
     
         21 . The method of  claim 20 , wherein the material of the reciprocating cylinder includes a porous heat transfer media, and
 transferring heat from the compressible fluid to the material of the reciprocating cylinder includes transferring heat to a porous heat transfer media within the reciprocating cylinder in intimate contact with the compressible fluid during isothermal compression, and   transferring heat to the liquid piston fluid includes transferring heat from the porous heat transfer media to the liquid piston fluid in intimate contact with the porous heat transfer media at least in the contracted position.   
     
     
         22 . The method of  claim 21 , wherein moving the reciprocating cylinder toward the contracted position relative to the static liquid piston includes infiltrating the porous heat transfer media with the liquid piston fluid. 
     
     
         23 . The method of  claim 19 , wherein extracting heat from the compressible fluid includes:
 spraying a heat sink fluid into the reciprocating cylinder,   extracting heat from the compressible fluid with the sprayed heat sink fluid, and   mixing the heated sprayed heat sink fluid with the liquid piston fluid according to settling of the heated sprayed heat sink fluid.   
     
     
         24 . The method of  claim 19 , wherein isothermally compressing the compressible fluid includes reciprocating the reciprocating cylinder relative to the static liquid piston at an operating frequency that decelerates the reciprocating cylinder at a deceleration greater than one gravity. 
     
     
         25 . The method of  claim 19 , wherein the static liquid piston includes a liquid piston fluid along a piston face and comprising retaining the liquid piston fluid along the piston face. 
     
     
         26 . The method of  claim 25 , wherein the liquid piston fluid includes a liquid piston ferrofluid, and retaining the liquid piston fluid along the piston face includes biasing the liquid piston ferrofluid toward the piston face with a retention magnet. 
     
     
         27 . The method of  claim 26 , wherein the reciprocating cylinder includes a porous heat transfer media, and
 retaining the liquid piston fluid along the piston face includes extracting the liquid piston ferrofluid from interstitial locations within the porous heat transfer media according to biasing of the liquid piston ferrofluid toward the piston face at least during retraction of the reciprocating cylinder from the contracted position.   
     
     
         28 . The method of  claim 26 , wherein retaining the liquid piston fluid along the piston face includes biasing the liquid piston ferrofluid toward a moving interface between the reciprocating cylinder and the piston face.